糖皮质激素受体与特发性血小板减少性紫癜患者激素抵抗的相关性

目的　探讨特发性血小板减少性紫癜(ITP)患者外周血单个核细胞(PBMC)内两种糖皮质激素受体(GR)α和β表达水平与糖皮质激素治疗效应之间的关系。方法　采用半定量RT PCR检测不同激素效应ITP患者和正常对照组GRα、βmRNA,采用免疫细胞化学方法检测GRα、β蛋白的表达。结果　(1)ITP激素敏感组、激素抵抗组及正常人体内均有GRα、βmRNA的表达,但以GRα为主, 其GRα/葡萄糖3磷酸脱氢酶(GAPDH)mRNA分别为1 15 ±0 75, 1 63±0 78, 1 27±0 51;(2)激素抵抗组GRβmRNA表达明显高于激素敏感组及正常对照组(P<0 05 ),其GRβ/GAPDHmRNA分别为1 42±0 73, 0 82±0 59, 0 80±0 68; (3)免疫细胞化学结果显示,激素抵抗组GRβ阳性细胞数明显高于激素敏感组及正常对照组(P<0 01 ),分别为28 8±9 9, 5 9±3 2, 5 5±6 8。结论　ITP患者糖皮质激素抵抗可能与GRβ的表达亢进有关。     

免疫抑制治疗无效的特发性血小板减少性紫癜患者血小板相关免疫球蛋白的亚型分析

目的分析糖皮质激素、环孢菌素A治疗无效的特发性血小板减少性紫癜(ITP)患者血小板相关免疫球蛋白(PAIg)的亚型。方法采用酶联免疫法(ELISA)对19992004年绵阳市中心医院收治的17例激素治疗无效、4例激素 环孢菌素A治疗无效以及30例激素治疗有效ITP患者的PAIg亚型进行检测。结果17例激素治疗无效的患者PAIg各亚型抗体较之激素治疗有效ITP患者差异有显著性(P<0·01),激素治疗无效组PAIg各亚型水平均明显增高;激素 环孢菌素A治疗无效组PAIgM较之激素治疗有效ITP患者有所增高(P<0·05)。结论激素治疗无效的ITP患者PAIg各亚型均显著增高,提示PAIg在介导ITP患者异常免疫反应过程中起重要作用,PAIg各亚型水平的增高可能有助于预测ITP患者对激素治疗的敏感性。     

激素依赖型哮喘患者临床和糖皮质激素受体特征

目的 探讨激素依赖（SD）型哮喘临床特征和单个核细胞（PBMC）糖皮质激素受体（GR）的水平。方法 26例激素依赖型哮喘,口服泼尼松20mg/d,7天,依据肺功能的变化,分为激素敏感（SS）型哮喘11例和激素抵抗（SR）型哮喘15例,比较两型临床、肺功能和PBMC的GR水平。结果 SS型和SR型哮喘在病史、肺功能和血嗜酸粒细胞方面差异无显性,SR型哮喘患PBMC的GR水平明显低于SS型哮喘患（P＜0．002）。结论 激素依赖型哮喘包括SS型和SR型哮喘,SR型哮喘GR水平异常低下是其特征。     

Low expression of glucocorticoid receptor alpha isoform in adult immune thrombocytopenia correlates with glucocorticoid resistance

The expression of glucocorticoid receptor (GR) isoforms has been linked to glucocorticoid (GC) resistance in various diseases treated with GC. However, existing data are conflicting in these diseases, and little information is available regarding immune thrombocytopenia (ITP). To further investigate the role of GR isoforms in GC resistance in adult ITP patients, we measured the mRNA expression of GR isoforms (GRα, GRβ, GRγ, GRp) in peripheral blood mononuclear cells (PBMC) from 54 newly diagnosed ITP patients, including GC-sensitive (GCS) and GC-resistant (GCR) patients and 35 healthy volunteers. The GRα and GRβ proteins in PBMC, nuclear factor-κB (NF-κB), and activator protein-1 (AP-1) in the nucleus were detected by Western blotting. Compared to normal subjects, both GRα and GRβ mRNAs were significantly increased in ITP patients (p?<?0.05), while there was no significant difference in the mRNA expression of GRγ and GRp. Compared to GCR patients, the expressions of GRα mRNA and GRα protein were significantly higher in GCS patients (p?<?0.05). Moreover, no significant difference in the mRNA expression of the GRβ, GRγ, and GRp isoforms was observed between GCS and GCR patients and the GRβ protein could not be detected. Compared to GCS group, the expression of p65/NF-κB was significantly higher in the GCR group (p?<?0.05). Overall, we did not find differences in c-Jun/AP-1 protein expression between GCS and GCR patients. In summary, GC resistance in adult ITP patients is associated with a reduced expression of GRα, which may be related with increased NF-κB. GRβ was very low and may not be involved in GC resistance in adult ITP, warranting further exploration.     

糖皮质激素受体α与激素量化治疗的初步研究

目的探讨31例系统性红斑狼疮（SLE）患者激素治疗前、后外周血单个核细胞（PBMCs）糖皮质激素受体α（GRet）的蛋白质水平、mRNA表达及其与疾病活动性的关系，分析GRot与SLE患者激素治疗疗效和剂量的关系。方法采用蛋白印迹（Western—blotting）和反转录-聚合酶链反应（RT-PCR）检测激素治疗前、后SLE患者和正常人外周血PBMCs中GRα蛋白质水平和GRαmRNA的表达，并将其与疾病活动性及激素剂量作相关分析。结果27例SLE患者激素敏感，4例激素耐药。激素敏感组PBMCs中GRα蛋白质水平和mRNA表达用药前高于用药后（P〈0．05），且与疾病活动性及激素剂量呈负相关。结论测定GRα的表达可能为激素的量化治疗提供依据。     

Perinatal management of idiopathic thrombocytopenic purpura in pregnancy: risk factors for passive immune thrombocytopenia

Summary Thirty-nine pregnant women with idiopathic thrombocytopenic purpura (ITP) were studied in order to evaluate the influence of therapies for maternal ITP on fetal passive immune thrombocytopenia (PIT). Neonatal platelet counts were also compared with platelet counts, amount of PAIgG, and presence of circulating antiplatelet antibody in maternal blood. Eight of 41 neonates (19.5%) presented PIT without neonatal mortality. A higher incidence of PIT was observed in women with prior splenectomy than in women without splenectomy (66.7% vs 11.4%). Neither a therapeutic effect nor an increased risk of PIT was observed with steroids or gammaglobulin administration. No correlation was found between neonatal platelet counts and maternal platelet counts or maternal PAIgG, while positive cases for circulating antiplatelet antibody assay presented a higher incidence of PIT than negative cases. Additionally, a higher incidence of PIT was observed in women with a history of previous PIT than in women with a history of normal delivery. Prior splenectomy, presence of antiplatelet antibody in maternal blood, and a history of previous PIT seem to be risk factors for fetal PIT.     

Role of glucocorticoids and glucocorticoid receptor in priming of macrophages caused by glucocorticoid receptor blockade

We previously reported that glucocorticoid receptor (GR) blockade (injected with GR antagonist RU486) primed the host responses to lipopolysaccharide. Since decrease of GR and elevated glucocorticoids (GCs) have been always reported as parallel responses, we hypothesize that both GCs and GR play important roles in GR blockade induced priming. We first confirm that the production of nitric oxide (NO), superoxide (O₂⁻), and PKCα expression are all increased in peritoneal macrophages from GR blockade rats, indicating that macrophages are primed by GR blockade. Furthermore, using unilateral adrenalectomy rats, we find that the elevated GCs caused by a feedback mechanism following GR blockade may be involved in the process of priming. In vitro experiments in RAW264.7 cells show the inhibitory effect of GCs on NO production, which can be thoroughly blocked by RU486, indicating the increase of NO production in GR blockade rats is due to the elimination of GCs’s anti-inflammatory function. In contrast, 10⁻⁷ M corticosterone induces significant increases in O₂⁻ release, PKCα expression and phosphorylation, which cannot be reversed by RU486, demonstrating a previously unrecognized pro-inflammatory role of GCs in enhancing PM activation through a GR-independent pathway. The effect of GCs on PKCα expression even exists in GR deficient COS-7 cells as well as in GR knock-down RAW264.7 cells. In conclusion, both GR impairment and elevation of GCs are involved in the priming of macrophages caused by GR blockade. The findings of the divergent roles of GCs in modulation of inflammation may change therapeutic strategy for inflammatory diseases with GCs.     

Immune thrombocytopenia and α-interferon therapy

Thrombocytopenia is often found in patients with liver diseases, especially due to congestive splenomegaly caused by portal hypertension. Immune thrombocytopenia has been described rarely, and it seems to be especially associated with hepatitis C virus, which has been described as having a particular interaction with the immune system contributing to the induction of autoimmunity. Interferons, on the other hand, because of their immunomodulatory properties, are able to induce or exacerbate autoimmune diseases. Mild thrombocytopenia is a common adverse effect of interferon therapy. Severe life-threatening thrombocytopenia is extremely rare. We report two cases of severe immune thrombocytopenia in patients with chronic hepatitis C, probably induced by α-interferon. Bone marrow aspirate and elevated platelet-associated IgG antibodies, determined by indirect immunofluorescence, were suggestive of immune thrombocytopenia. None of the patients had any clinical sign of autoimmune syndrome, including arthritis, serositis, Sicca syndrome, vasculitis, thyroid abnormalities and others. Cryoglobulins and rheumatoid factors were tested and were undetectable. The patients' histories of exposure to α-interferon and the exclusion of other causes are most consistent with drug-induced immune thrombocytopenia. After α-interferon withdrawal, thrombocytopenia was treated successfully with prednisolone and immunoglobulins. Response to treatment was consistent with the diagnosis of α-interferon-induced immune thrombocytopenia and peripheral consumption of platelets.     

Helicobacter pylori-associated immune thrombocytopenia:Clinical features and pathogenic mechanisms

Immune thrombocytopenia(ITP)is an autoimmune disease mediated by anti-platelet autoantibodies.There is growing evidence that the eradication of Helicobacter pylori(H.pylori)effectively increases platelet count in a considerable proportion of ITP patients infected with this bacterium.In the majority of ITP patients responding to H.pylori eradication therapy,the anti-platelet autoantibody response is completely resolved with no relapse for more than 7 years,indicating that the disease is cured.Therefore,adult patients with suspected ITP should be examined for H.pylori infection,and eradication therapy is recommended if the infection is present.Notably,however,the efficacy of H.pylori eradication therapy in ITP patients varies widely among countries,with a higher response rate in Japan compared with the United States and European countries other than Italy.The pathogenesis of H.pylori-associated ITP is still uncertain,although the mechanisms are known to involve multiple factors.H.pylori may modulate the Fcγ-receptor balance of monocytes/macrophages in favor of activating Fcγreceptors,and H.pylori components may mimic the molecular makeup of platelet antigens.Further studies of the pathogenic process of H.pyloriassociated ITP may be useful for the development of new therapeutic strategies for ITP.     

Thrombopoietin and its receptor expression in pediatric patients with chronic immune thrombocytopenia

Objectives: Chronic immune thrombocytopenia (cITP) is common in children. However, the pathogenesis has not been fully elucidated. This study aimed to determine whether thrombopoietin (TPO) and its receptor c-mannosylation of the TPO receptor (c-Mpl) have an impact on childhood cITP.

Methods: Sixty-four patients with newly diagnosed ITP (nITP), 64 patients with persistent ITP, 80 patients with cITP, and 64 healthy children (control) were enrolled in this study. Plasma TPO was measured with an ELISA, and c-Mpl was determined by flow cytometry.

Results: Plasma TPO levels showed differences among the four groups (p?=?0.001). TPO levels in the cITP group were significantly decreased compared to those in the nITP group (p?p?=?0.0275). c-Mpl MFI was lower in the cITP group than in the nITP group(p?p?p?=?0.023). The control group, compared with the other groups, had lower levels of c-Mpl mRNA.

Conclusions: The expression of TPO and c-Mpl was significantly decreased in the cITP group compared to the nITP group, suggesting that TPO and its receptor may play important roles in childhood cITP pathogenesis.     

冷束缚应激状态下大鼠内源性糖皮质激素与肠屏障功能损害的关系

目的观察冷束缚应激(cold restrain stress,CRS)状态下大鼠血清皮质醇浓度及肠屏障功能的改变情况,以及糖皮质激素受体阻断剂(RU38486)对CRS状态下大鼠肠屏障功能的影响。方法60只成年雄性SD大鼠,随机分为正常对照组、应激组(S组)和糖皮质激素受体阻断剂组(R组)。S组和R组按应激后检测时间又分为S2 h、S4 h、S8 h、S16 h、S24 h组和R2 h、R4 h、R8 h、R16 h、R24 h组。应激动物模型参照Brodie[1]的方法改良制作。动态观察各组大鼠的血皮质醇浓度变化及肠黏膜屏障功能的改变情况。结果应激组各时段大鼠血清皮质醇浓度、D-乳酸浓度、血浆内毒素浓度及肠黏膜损伤指数均高于正常组,而糖皮质激素受体阻断后血清皮质醇浓度、D-乳酸浓度、血浆内毒素浓度及肠黏膜损伤指数均较应激组相应各时段明显增高。结论应激可以造成肠黏膜上皮的损伤,导致肠黏膜屏障通透性增高,糖皮质激素受体阻断剂则进一步加重肠屏障功能的损害,表明应激产生的血清皮质醇对肠屏障功能起着保护性的作用。     

人参皂甙逆转糖皮质激素下调其受体的实验研究

目的 观察人参皂甙(GS)对糖皮质激素(GC)下调其受体(GR)的影响,并探讨其作用途径.方法 建立大鼠肝总动脉结扎模型,分别给予GS和地塞米松(DEX)等药物干预,观察术后12 h各组血清皮质酮、肝脏GR最大结合容量(GR Bmax)、平衡解离常数(K<,d>)和GR mRNA水平.结果 GS组和模型组皮质酮水平明显高于GS+DEX组、DEX组和正常组(均P<0.01),GS+DEX组和DEX组皮质酮水平明显高于正常组(均P<0.01);GS组GR Bmax高于模型组(P<0.05),Gs+DEX组GR Bmax明显低于模型组(P<0.05),但高于DEX组(P<0.01);GS组GR mRNA表达明显高于模型组(P<0.01),DEX组则低于模型组、正常对照组和GS+DEX(P<0.01).结论 GS虽然对肝缺血损伤大鼠血清皮质酮水平无影响,但可以部分逆转GC对GR的下调作用.     

急性肺损伤与糖皮质激素受体的研究进展

急性肺损伤/急性呼吸窘迫综合征（acute lung injury/acute respiratory distress syndrome,ALI/ARDS）是指心源性以外的各种肺内外致病因素所致的毛细血管膜及肺泡内皮损伤导致肺水肿和肺不张,以呼吸窘迫和顽固性低氧血症为临床特点的呼吸衰竭。糖皮质激素（glucocorticoid,GC）可作用于ALI/ARDS的多个发病环节,早期可用于ALI/ARDS的治疗,但疗效差异很大,一直存在争议,具体机制尚未清楚。近年来认为GC治疗ALI/ARDS的疗效与其受体数量及亲和力之间存在一定的关系。为此,就ALI/ARDS与糖皮质激素受体（glucocorticoid receptor,GR）二者关系进行综述,对于阐明GR的作用机制以及提出激素治疗指征具有重要意义。     

Markers of refractory primary immune thrombocytopenia

Refractory immune thrombocytopenia (ITP) is a challenging disease that can be defined by refractoriness to second-line treatments. In this review, we list and comment available evidence about clinical and biological factors associated with refractoriness to splenectomy, thrombopoietin receptor agonists (TPO-RAs), rituximab and fostamatinib, as well as those associated with multirefractory ITP (active disease with failure of rituximab, TPO-RAs and splenectomy).